Static Bending and Flexural Fatigue Strength of CFRP Aluminium Honeycomb Sandwich Beams

Abstract

Test results are presented on the static bending strength and the flexural fatigue strength of a honeycomb sandwich beam consisting of an aluminium honeycomb core and graphite fiber reinforced plastic facings. The static bending strength was measured by an Instron-type testing machine, Shimadzu AUTOGRAPH IS-20T, and the low cycle flexural fatigue strength was measured by the AUTOGRAPH IS-20T and an electro-hydraulic testing machine, Shimadzu SERVOPET Lab-5. In the flexural fatigue test under the bending stress “R=0.1”, a piece of rubber plate of 35 mm in length, 30 mm in width, and 3 mm in thickness was attached at each loading point on the CFRP aluminium honeycomb sandwich beams in order to prevent undesirable damages on the sandwich beams due to the concentrated loading. It was found that the static bending strength as well as the flexural fatigue strength of the honeycomb sandwich beams depends mainly on the properties of the facing materials. It was also found that the CFRP aluminium honeycomb sandwich has a sufficiently high strength in both static bending and flexural fatigue to be used as a structural component.